1. Field of the Invention
The present invention relates to status information in wireless (mobile) communication systems. More particularly, it relates to a method for storing the status information of a transceiver in a base station of the wireless communication system.
2. Description of the Related Art
A PCS (Personal Communication Services) system and a CDMA (Code Division Multiple Access) system comprise a number of Base Transceiver Systems (BTSs) which provide services to Mobile Stations, a Base Station Controller (BSC), a Base Station Management System (BSM) which manages a number of BSCs, a Mobile Switching Center (MSC), and a Location Register (LR) system.
The area that each BTS services is called a cell, and the cell is divided into several sectors. The cell is expanded to BTS, BSC, MSC service areas in order.
In a mobile telecommunication system, the MSC system and other systems generally make up a Base Station Subsystem (BSS). The BSS includes the BSM, BSC and BTS in order of precedence. The main processor of the BSC is called a Call Control Processor (CCP) and the main processor of the BTS is called the BTS Control Processor (BCP).
The base station transceiver is a module included in the radio frequency unit of the base station subsystem (BSS) in a CDMA mobile system. The transceiver includes a Transceiver Master Control Unit (XMCU) controlled by a Transceiver Interface Processor (TIP), and a Transceiver Unit (XCVU) controlled by a Transceiver Unit Processor (TRUX).
The TIP receives data from the BCP to generate RF signals and transmits them to the transceiver. The TIP refers to the processor that controls the XMCUs, and the TIPX refers to a software block which is loaded in the TIP. The TIPX also receives transceiver status information and alarm information from the transceiver and transmits the same to the BCP. The TIP is a dual processor having two sides (e.g., A and B), each functioning as an independent processor. That is, one side (e.g., A) is active while the other side (e.g., B) is in a standby state. When a fault occurs in the active side A for whatever reason, the side B (standby side) is activated and side A is placed in the standby state. The TIP downloads the TIPX program from the BCP and activates the respective side when a fault occurs.
The TRUX receives status information of a base station transceiver from the TIPX, and reports the frequency of the transceiver, an output adjustment, an alarm detection and the transceiver status to the TIPX. At the same time, the TRUX performs the function of displaying the transceiver status on an LED such as a 7-segment attached to the front side of each XCVU board. The TRUX also performs monitoring of equipment or non-equipment status of each XCVU board in the base station transceiver, and monitors and controls the PLL locking status and output adjustment.
A base station transceiver can perform a frequency assignment service in a sector.
The BTS Status Handling (BSHX) block, which is a status management block in the BCP, receives a status information message of the base station transceiver from the TIPX, and manages the status of the transceiver. The status of a base station transceiver affects the management of a subcell on the basis of the identifier of the sector including a specific transceiver and the identifier of the CDMA channel. Thus, if the status of a base station transceiver is abnormal, the status of the corresponding subcell also becomes abnormal.
There are several types of base station systems according to the number of the TIPXs and transceivers. A conventional base station transceiver belongs to one of two types (i.e., type 1 or type 2).
A type 1 base station, of an earlier standard base station type, supports a maximum of three sectors and four frequency assignments. To implement five or more frequency assignments, a rack of the same form is needed. The type 2 base station, of the micro base station type, supports a sector, a frequency assignment and no redundant transceiver.
FIG. 1 illustrates the stored status information of a transceiver in a conventional type1 base station. As illustrated, rack1 (110) includes TIP0, TIP1 and TIP2 which each perform the frequency assignment 0 (FA0), the frequency assignment1 (FA1), the frequency assignment2 (FA2) and the frequency assignment3 (FA3), and rack2 (120) includes TIP3, TIP4 and TIP5 which each perform the frequency assignment4 (FA4), the frequency assignment5 (FA5), the frequency assignment6 (FA6) and the frequency assignment7 (FA7). Each TIPX has a redundant (R) transceiver (XCVR0) and four transceivers (XCVR1-XCVR4) for each of the respective frequency assignments. In the type1 system, a rack includes three TIPXs and the transceivers under each of the TIPXs. As illustrated in FIG. 1, two racks (110 and 120) are used to support eight frequency assignments (FA0-FA7).
FIG. 2 illustrates the stored status information of a transceiver in a conventional type2 base station. As illustrated, a rack is composed of a TIPX and a transceiver for processing a frequency assignment.
A BSHX block has a sector identifier such as xcex1, xcex2, xcex3 for each transceiver, and a CDMA channel identifier such as 0, 1, 2, 3, 4, 5, 6, 7. The BSHX block stores the status information of a transceiver from the TIPX in the position designated by the identifiers as a specified table.
FIG. 3 illustrates a status information table of a TIPX and a transceiver stored in the BSHX block. As illustrated, the status information according to the identifier of each TIPX and the identifier of each transceiver are stored in the specified format. In case of type1 and type2 system, i is an identifier of the TIPX and j is an identifier of a transceiver, where [i, j] is a key to retrieve the status information in the table.
In a type1 system, the status information from a transciever0 (XCVR0) to a transceiver4 (XCVR4) in each TIPX is stored in the position of the table according to each identifier, and the transciever0 (XCVR0) becomes redundant. But in a type2 system, only the status information of a transciever0 is necessary, and transciever0 is not redundant.
According to an improvement of the system, the type2 system has been substituted by a type3 and type4 system. In these systems, the maximum number of transceivers is increased to six per conventional TIPX and there is no redundant transceiver, so the message format and the relation scheme of the database are changed.
FIG. 4 illustrates the stored status information of a transceiver in a type3 base station. As illustrated, rack1 (410) can support a frequency assignment (FA0) and three sectors (xcex1,xcex2,xcex3) and rack2, rack3 and rack4 (420, 430, 440) can support two frequency assignments and three sectors for each frequency assignment. In FIG. 4, four racks are used to support seven frequency assignments (FA0-FA6) and three sectors. Thus, the type3 system can support a maximum of two frequency assignments and three sectors in a rack.
If a system supporting a frequency assignment and three sectors is needed, a TIPX and three transceivers can be used.
FIG. 5 illustrates the stored status information of a transceiver in a type4 base station. As illustrated, a type4 system is a system of small Omni-directional base station type and rack1 (510) can support three frequency assignments (FA0-FA2) and rack2 (520) can support four frequency assignments (FA3-FA6). Therefore, seven frequency assignments can be supported using two racks.
A database to store the status information of a base station transceiver is physically organized according to the system configuration. Thus, if the system configuration is changed, the message format used to communicate with the TIPX must also be changed. Therefore, according to the above, a table in the corresponding database should be changed which makes and it is necessary to find an identifier of the sector including a transceiver, and an identifier of a CDMA channel for every processing of the subcell.
Consequently, in managing of the status of a transceiver that can be changed according to the system, an additional operation must be performed in response to the change of system configuration.
The present invention for solving the above problem provides a method for storing the status information of a transceiver in a base station. Particularly, this invention is intended to provide a method for creating the table in which the status information can be stored for any type of system by organizing the database that stores the transceiver status information on the basis of a sector identifier and the identifier of the CDMA channel that each transceiver can perform services. Additionally, it is intended to provide a method for flexibly storing the status information of a transceiver for any system configuration by making the subroutine to find the sector identifier and the CDMA channel identifier that serve as a key to the created table.
In one embodiment, the method for storing status information of a transceiver in a base station comprises the steps of: receiving a transceiver status message from a transceiver interface processor; retrieving a system type from Program Load Data (PLD); finding a value of i as an identifier of a sector and a value of j as an identifier of a CDMA channel according to each system type; and creating a status information table of the transceiver in the base station such that each value of [i,j] derived from the finding step serves as a key to the table.
In the embodiment, it is preferable that the system type is one of the type1, type2, type3 and type4 systems. When using a type1 system, the steps for finding the values of i, j and creating the status information table of the transceiver in the base station further comprise the steps of: comparing the value of TIP_ID as an identifier of a transceiver interface processor with a first specific value; setting the identifier i in response to the comparison; comparing the value of XCVR_ID with a second specific value; setting the identifier, j in response to the comparison; and storing the status information to the location of [i, j].
The first specific value compared to the value of TIP_ID is preferably 3, and if the value of TIP_ID is less than 3, i is set to the value of TIP_ID. Otherwise, i is set to a value equal to TIP_ID divided by the maximum number of sectors in the base station. The second specific value compared to the value of XCVR_ID is preferably 0, and if the XCVR_ID value is zero, j is set to 8, otherwise j is set to the value of (XCVR_IDxe2x88x921).
When using a type2 system, the steps for finding the values of i, j and for creating the status information table of the transceiver in the base station further comprise the steps of: setting the identifiers, i and j, to a first and second specific value, respectively; and storing the status information to the location designated by [i, j]. In the type2 system, the first and second specific values to which the identifiers, i and j are set is zero, respectively.
When working with a type3 system, the steps for finding the values of i, j and for creating status information table of the transceiver in the base station further comprise steps of: comparing the value of TIP_ID with a first specific value; comparing the value of XCVR_ID with a second specific value; setting the identifiers, i and j in response to the comparisons, respectively; and storing the status information to the location of [i, j].
The first specific value compared to the value of TIP_ID is preferably 0, and the second specific value compared to the value of XCVR_ID is preferably 3. If the value of TIP_ID is not equal to zero or if the value of XCVR_ID is greater than or equal to 3, then the process returns to the step of receiving the transceiver status message from the transceiver interface processor.
When working with a type4 system, the steps for finding the values of i, j and for creating status information table of the transceiver in the base station further comprise the steps of: comparing the value of TIP_ID with a first specific value; comparing the value of XCVR_ID with a second specific value; setting the values of i and j in response to the comparisons; and storing the status information to the location of [i, j].
The method further includes a step of setting the identifiers, i and j to the first and second specific values, respectively, after the value of TIP_ID is compared with zero and the value of TIP_ID is equal to zero. If the value of TIP_ID is not equal to zero, then the value of XCVR_ID is compared with the second specific value.
The first specific value compared to the value of TIP_ID is preferably 0, and the second specific value compared to the value of XCVR_ID is preferably 3.
If the value of TIP_ID is equal to 0, the sector identifier i is set to the value of XCVR_ID and the CDMA channel identifier j is set to zero (0). If the value of TIP_ID is not equal to 0, the value of XCVR_ID is then compared with the second specific value of 3. If XCVR_ID is less than 3, the sector identifier i is set to XCVR_ID and the value of CDMA channel identifier j is set to TIP_ID*2xe2x88x921. If the value of TIP_ID is not equal to the first specific value and the value of XCVR_ID is not less than the second specific value, identifier i is set to the value of XCVR_ID divided by the second specific value, and identifier j is set to a value resulting from multiplying TIP_ID by 2 (i.e., TIP_ID*2).